To obtain a Sergeant's Insignia, you need to find and kill any Fatiu at Level 40+. Anything above Lvl 40+ also has a chance to drop Recruit's Insignia.
You can get these from any of the Fatui Family, such as Agents, Cicin Mages, and Skirmishers.
To get any Fatui to become Lvl 40+, you need your World Level to become World Level 2 or higher. The most efficient WL to farm is WL 4, as enemies are between Level 42 and 62. This will give you the most consistent enemy Lvl past 40+.
To get to WL 4, you need to have completed the following.
- Be on World Level 3
- Be Adventure Rank 35
- Clear Ascension Quest 2
The fastest way to get around is to use the Waypoints, kill everything in sight, and then move on. The two images below are where you can find Fatui in both Mondstadt and Liyue.
Just click on them to enlarge them.
Thanks to Map Genie Genshin Impact Interactive Map!
- Type: Common Ascension Material
Using an Alchemy Table, you can turn lower tier materials into higher tier materials.
Recruit’s Insignia is used for the following Character Ascensions.
Each Common Ascension Material has three tiers; these are the tiers above and below Sergeant’s Insignia.